Genesis 27:1

When Isaac was old. From the following considerations, Isaac must have been about 137 years of age when the incident narrated in this chapter took place. Esau was already married (v. 46). This occurred when Isaac was 100 years old (see chs. 26:34; 25:26). But, as will be seen, the events recorded here must have occurred at a much later time even than that. Jacob was 130 years old when he went down to Egypt (ch. 47:9), and his son Joseph 39. This is clear from the fact that the latter was 30 years old when he entered the service of Pharaoh (ch. 41:46), and that since that time 7 abundant and 2 lean years had passed (chs. 41:54; 45:6). These 9 years must be added to the 30, making Joseph 39 years of age. Jacob was consequently 91 years old when Joseph was born. This had taken place at the end of 14 years of Jacob’s service in Laban’s house (chs. 29:18, 27; 30:25); therefore Jacob was 77 years old when he fled to Haran. Since Jacob’s flight probably followed soon after the events of this chapter, and since his father Isaac was 60 years old when Jacob was born (ch. 25:26), Isaac’s age in ch. 27 must have been about 137 years. Isaac lived for another 43 years, to the ripe age of 180 (ch. 35:28).